- Do not put statements in the negative form.
- And don’t start sentences with a conjunction.
- If you reread your work, you will find on rereading that a great deal of repetition can be avoided by rereading and editing.
- Never use a long word when a diminutive one will do.
- Unqualified superlatives are the worst of all.
- De-accession euphemisms.
- If any word is improper at the end of a sentence, a linking verb is.
- Avoid trendy locutions that sound flaky.
- Last, but not least, avoid clichés like the plague.
(From Great Rules of Writing by William Safire)